Components in transmission systems of heavy-duty machines are often subjected to abnormal torque and other forces during operation. Specifically, a transmission shaft in such a transmission system is often susceptible to excessive wear. Also, improper manufacturing processes, such as inadequate heat treatment or the like, may also be the cause of early failure of the transmission shaft. For these reasons, a transmission shaft sometimes experiences cracks and other failures despite advanced metallurgical processing techniques and other engineering approaches that are used to avoid such failures. In general, a transmission shaft failure will cause failure of the machine as a whole. This creates excessive idle-time costs to operators of such machines. Accordingly, it is important that such machines are in service as much as possible.
Various methodologies for testing transmission systems are known in the art. For example, ultrasonic flaw detection apparatus may be used to detect cracking and other defects in materials, such as is described in U.S. Pat. No. 5,511,425, entitled “Flaw Detector Incorporating DGS.” The described flaw detector involves generation of a sound wave or pulse and transmitting the pulse through a transducer to the material under inspection. The transducer then listens for an echo signal that provides information concerning the material under consideration. However, these flaw detectors are often used in test procedures that involve disassembly of the transmission system in order to inspect the various components in detail. While this is suitable for discovering cracking or other failures in the transmission shaft, such procedures are somewhat costly and often time consuming. They further require skilled personnel in order to perform the testing.